The present invention relates generally to devices for producing tension in a line, and more particularly to such a device which is simple, inexpensive and portable and primarily usable in tightening cable, rope, webbing and similar lines in retaining a load in place on a vehicle.
In its preferred form hereinafter described and illustrated, the invention includes a pair of spaced plates of metal or equivalent material, typically generally rectangular in shape and held in spaced parallel relation by a pair of studs, one near each of two opposite ends of the plates, fixed to the plates and extending therebetween. Each of the studs projects beyond one of the plates to provide anchoring points for application of a crank used in applying torque to the tensioner and in removing torque therefrom. One of the plates has fixed thereto a bracket or ear lying in the plane of the plate and extending outwardly from the generally rectangular outline of the plates. A swing arm is pivotally attached to the bracket ear for swinging or pivoting movement in a plane parallel to that of the bracket ear itself, and the distance between the pivotal axis and the line joining the two studs is large compared to the thickness of the line as it is curved partially around the studs in use. The distal end of the swing arm has attached thereto one end of the line, which then passes through an eye of a hook (or alternatively, around a pulley attached to a hook) and then between the plates of the body of the tensioner. The other end of the line is made fast to a distant part of the vehicle carrying the load, and the hook is similarly fastened to the vehicle, with the major length of the line passing over the load. Twisting the tensioner about its own axis then serves to impose tension on the line, and such twisting is accomplished by a crank temporarily attachable to the projecting portions of the studs. When fully tensioned the device is inherently in balanced equilibrium, and will resist any tendency to become loosened by reason of movement or swaying of the load while it is being transported.